Gareth Brown

Facebook has had custom audiences for while now.  You can create a Custom Audience using email addresses, phone numbers, Facebook user IDs or mobile advertiser IDs.

https://www.facebook.com/help/633474486707199/

How we charge for our time isn't the issue here, its more about the value of the work we do. The removal of a single link shouldn't cost a site owner $300, $125 or even $50. Anyway, thats how I feel about it.

With regards to you last comment:

( I actually do lots of free work and advice for startup businesses - not as much of a monster as I sound just have a nagging suspicion that the majority of the sentiment about responding to random email requests come from a segment of self professed SEO's that have lots of free time on their hands)

I'm sure you weren't referring to Chris! :)

Your setup isn't much different from any other web development company. If it took my guys anymore than 10 minutes to remove a link, we'd never get any productive work done.

Validating the request is easy - did it come from the domain? If not, ask them to resend using the correct email address.

Accidental site wides are another issue all together. I personally feel it's the website owners responsibly to remove the links if there's a fault with a widget or CMS - especially if it's possibly hurting someone's business. These removal requests are completely valid and shouldn't be charged for. 

At the end of the day, it's your site and you can do whatever you want. 

Karma........

Threats of disavow and DMCA takedowns are BS, very unprofessional, and probably not the best way to start the conversation!  

You are right; I'm being compensated to remove the links, so I personally dont have an issue with paying for links to be removed - at the right price.  id rather they were gone, and never to appear again! BUT $125! If thats not extortion, what is it? Removing a link or deleting a page shouldnt take any more than 10 minutes...at most. 

At least they do reply! The ones that don't are just rude :)